Copper silicon manganese alloy



Patented Nov. 21, 1933 UNITED STATES 1,936,397 COPPER SILICON MANGANESE ALLOY Herbert C. Jennison, Bridgeport, Conn., assignor to The American Brass Company, Waterbury, Conn., a corporation of Connecticut No Drawing. Application September 8, 1932 Serial No. 632,190

6 Claims.

much greater strength than copper and still has workability, toughness and other desirable characteristics and physical properties.

It has been known to alloy relatively large amounts of silicon and manganese with copper 10 and the resulting alloys are 'very valuable and have desirable characteristics for certain uses but have certain limitations. In these alloys the silicon content was above 3.0% and the manganese above 0.5%.

I have discovered that there is a range of alloys containing much less silicon and manganese which have desirable characteristics and physical properties not present in the alloys above men tioned. In particular these new alloys can be drawn, cold rolled or cold worked a much greater amount between annealings and therefore can be fabricated into various articles at much less expense. These alloys also have a number of other desirable characteristics.

For example, I can use these alloys as a substitute for manycopper-zinc alloys known as brass. Under certain conditions some of the brasses are liable to season cracking or corrosion cracking, while my new alloys are not subject to this behavior. As stated above these new alloys may be drawn, cold rolled or cold worked a very great amount between annealings, and in 'fact, extreme strength and hardness may be obtained by omitting annealing without the danger of season cracking or corrosion cracking.

In my alloy I add silicon to the copper in amounts from 0.1% to 2.5% and manganese from 0.01 to 0.45%. The silicon gives the alloy hardness and increased strength while the manganese increases its workability hardness, toughness, etc.

As a specific example, I have found an alloy containing approximately 99.00% copper, 0.75% silicon and 0.25% manganese has very desirable properties. It has strength and hardness and can be cold worked without frequent annealings.

Another example which has been found to have highly desirable properties has approximately the following composition: copper 98.25%. silicon 1.50% and manganese 0.25%. This alloy has been found to be very desirable for making such articles as bolts. The wire or rod can be drawn very hard to obtain a high tensile strength, and then can be cold headed and threaded. The alloy is so ductile that cold heading in addition to the large amount of drawing does not render the bolts brittle. This alloy is also very desirable for making nails and screws. These nails can be used in any way that an iron nail can be used and. we have the added advantage of the material being non-corrosive. This alloy is also very useful for seamless tubes and pipe.

Still another specific example which has been found desirable for certain uses contains approximately the following proportions: copper 99.25%, silicon 0.50% and manganese 0.25%.

In addition to being capable of extensive drawing, rolling and other cold working without anhealing, and having the other properties above mentioned, my new alloy is suitable for welding, and welding rod may be made from the material for general welding work. It may be welded electrically, with gas, or spot welded into various articles, such as tanks, boilers, tubes, architectural shapes, etc. It may also be brazed.

The alloy has a higher resistance to corrosion 75 than copper, and the additions of silicon and manganese to the copper make the alloy much stronger, harder and tougher'than pure copper would be.

I have also discovered that much sounder castings for working into wrought forms and shapes can be made with my new alloy than can be obtained with the higher silicon alloys mentioned. My new alloy is suitable for sand casting work as well.

This new alloy within the range of elements mentioned can be made into tubes by the Mannesmann process or by the extrusion process when heated to suitable temperatures. This alloy may also be hot rolled or extruded into rods and various shapes for all purposes. It may also be hot pressed and hot forged into various shapes.

On account of the high tensile strength and elastic limit of my alloy it has been found to be particularly suitable for the manufacture of cartridge shells and cases for ammunition. The alloy has a high resistance to mercury used in the fulminate and also a high resistance to the explosive forces in the powder used in cartridge WOi'k.

.The above are merely some examples of the many uses for which this new alloy is adapted on account of its desirable characteristics and physical properties.

Having thus set forth the nature of my invention, what I claim is:

1. A copper base alloy comprising from about 0.1% to about 2.5%silicon, from about 0.01% to about 0.4% manganese, and the balance substantially all copper.

to approximately 1.50% silicon, and balance substantially copper.

6. A copper base alloy which is capable of extenslve drawing, rolling and other cold working without annealing composed of 0.1% to 2.5%

silicon, irom 0.01% to 0.4% manganese, and the balance substantially copper.

HERBERT C. JENNISON. 

